Honda ruckus won't start, what are troubleshooting steps?

I have a 2009 Honda Ruckus that won't start reliably. The battery is dead for sure, but the kick start works occasionally. Problem Description -To get it to start I have to take it of of the barn and let it sit in the sun for a few hours. Then I'll have to try and kick start it about 3 or 4 times over the course of the next couple hours - give a couple tries, let it sit for awhile, then try again. Then it will eventually start, and I can ride around (but it will stall at idle within the first few minutes).
Troubleshooting- I've never done any maintenance on it, so I want to start there. I found videos on how to change spark plug and coolant, so I will do that today. What are some other troubleshooting steps to try? Please link videos if possible, because I'm not mechanically inclined and need to be taught like a child! Ha.

Gotta be fuel, spark, air, bad / loose / corroded connections, cracked / loose rubber parts, plugs and valves that need to be gapped, etc. It's much easier to see problems on a clean bike (that's been given a good brushing with a bucket of soapy water, and rinsed). Get a Haynes, Clymer, or Honda (or all three) shop manual. You're gonna need the right tools to do a tuneup. No tools? No manuals? Take it to a dealer for service.

Get a new battery. Key ON, check if the lights work and the cluster is bright. Put a new air filter and fuel filter. Change the oil. Remove the spark plug, spray starting fluid on the chamber and install a new plug. Try to start. Bike starts and dies, check the carb. Check if the carb is getting fuel. Bike does not start, check for spark.

It needs a battery to run. Check that after you replace the battery. Check for fuel, spark, timing and compression. Take it to the shop since you have no mechanic skills or tools.

You know it will start and run which is good.

So get a replacement battery;
Change the oil;
Change spark plug;

If it runs properly then you need to make sure that it stops. That could involve new pads and new fluid.

Then you can change all the other fluids, make sure it is not leaking anywhere.

Then check all the electrics work.

Change spark plugs, air filter, oil, and oil filter, then dismantle the carbs (if fitted) and blow out the jets.
If it has fuel injection get a petrol injector cleaner and mix with petrol.
Also make sure the fuel line is allowing free-flow and that the pinhole in the fuel cap is not blocked.
These measures should see the bike running properly. If you're not feeling competent to undertake these jobs then take it to a dealer for a service.

PS. Get a new battery!

Nothing mechanical will run forever without servicing & maintenance. Give the poor thing some TLC. Change the oil,& filter, replace the spark plug (get the right one), give it a new air filter. Replace the battery.
The best way to do all this is either take it t oa mechanic or buy a or or otherwise obtain a workshop manual for the bike & READ IT.

For you? Get $100.00 bill and 6 pack of root beer, trailer it to Honda shop and give the $100.00 bill direct to head mechanic and ask for a maintenance lesson, whimper and beg if needed so you can observe and take notes of oil change, filters, spark plugs, battery work, tire checks. The mechanic will need a extra hour or two to tell you what was done and why- that is where the root beer will come in handy, hydration while talking. Regular shop bill paid by check or credit card- cash to mechanic that may or may not tell revenuers about class in maintenance second job. Might have to split with dealer just for the extra insurance coverage. Next rip to shop will require a 6 pack of same or other beverage -Coors or Spotted Cow. You'll learn by doing some- mech may have you pull spark plug, check, replace, do oil change next time. That is basis for trouble shooting education, moderate tuition costs and little ruckus will be happier.

the kick starts the lights an horn works while running new battery but will not start it only starts when you kick start it